Active tilting-pad journal bearings with radial oil injection combine good stability properties of conventional tilting-pad journal bearings with the capability of improving their dynamic properties even more by control techniques. The main contribution of this work is the experimental investigation of integral controllers for feedback-controlled lubrication with the aim of: a) presetting the static journal center and consequently exploring the changes of bearing dynamic properties; b) obtaining an integral controller capable of re-positioning the static journal eccentricity for matching equilibria under conventional hydrodynamic and feedback-controlled lubrication regimes. A novel application is proposed, that tries to build “non-invasive perturbation forces” and uses the active fluid film forces of the bearing as a “calibrated shaker”.
HaggAC. The influence of oil-film journal bearings on the stability of rotating machines. J Appl Mech Trans ASME1946; 13(3): A211–A220.
2.
Ulbrich H and Anton E. Theory and application of magnetic bearings with integrated displacement and velocity sensors. In: 3th International Conference on Vibrations in Rotating Machinery. IMechE. Heslington, Yorkshire, C299/84, 11--13 September 1984, pp.543--551.
3.
Ulbrich H and Althaus J. Actuator design for rotor control. In: 12th biennial conference on mechanical vibration and noise, Montreal, Quebec, Canada, 7--21 September 1989, pp.17–22.
4.
PalazzoloALinRRAlexanderRM. Test and theory for piezoelectric actuator-active vibration control of rotating machinery. J Vibration Acoust1991; 113(April): 167–175.
5.
Althaus J and Ulbrich H. A fast hydraulic actuator for active vibration control. In: 5th International Conference on Vibrations in Rotating Machinery. IMechE. Bath, C432/045, 7--10 September 1992, pp.141--148.
6.
SantosIFDesign and evaluation of two types of active tilting pad journal bearings. In: BurrowsCRKeoghPS (eds). The active control of vibration, London: Mechanical Engineering Publications Limited, 1994, pp. 79–87.
7.
SantosIFRussoF. Tilting-pad journal bearing with electronic radial oil injection. J Tribol Trans ASME1998; 120(July): 583–594.
8.
SantosIFScalabrinA. Control system design for active lubrication with theoretical and experimental examples. J Eng Gas Turbines Power2003; 125(1): 75–80.
9.
SantosIFNicolettiRScalabrinA. Feasibility of applying active lubrication to reduce vibration in industrial compressors. J Eng Gas Turbines Power2004; 126(October): 848–854.
10.
SantosIFWatanabeFY. Compensation of cross-coupling stiffness and increase of direct damping in multirecess journal bearings using active hybrid lubrication: part I-theory. J Tribol2004; 126(January): 146–155.
11.
SantosIFNicolettiR. Control system design for flexible rotors supported by actively lubricated bearings. J Vibration Control2008; 14(3): 347–374.
12.
HaugaardAMSantosIF. Elastohydrodynamics applied to active tilting-pad journal bearings. J Tribol2010; 132(2): 021702–1–10.
13.
HaugaardAMSantosIF. Stability of multi orifice active tilting-pad journal bearings. Tribol Int2010; 43(9): 1742–1750.
14.
HaugaardAMSantosIF. Multi-orifice active tilting-pad journal bearings Harnessing of synergetic coupling effects. Tribol Int2010; 43(8): 1374–1391.
15.
Cerda VarelaASantosIF. Stability analysis of an industrial gas compressor supported by tilting-pad bearings under different lubrication regimes. J Eng Gas Turbines Power2012; 134(2):): 022504–1–11.
16.
Cerda VarelaABjerregaard NielsenBSantosIF. Steady state characteristics of a tilting pad journal bearing with controllable lubrication: comparison between theoretical and experimental results. Tribol Int2013; 58: 85–97.
17.
VarelaACSantosIF. Performance improvement of tilting-pad journal bearings by means of controllable lubrication. Mech Ind2012; 13(1): 17–32.
18.
Varela AC, Fillon M and Santos IF. On the simplifications for the thermal modeling of tilting-pad journal bearings under thermoelastohydrodynamic regime. In: ASME Turbo Expo 2012, Copenhagen, Denmark, 11--15 June 2012, pp.823--835.
19.
KeelLHBhattacharyyaSP. Controller synthesis free of analytical models: three term controllers. IEEE Trans Automatic Control2008; 53(6): 1353–1369.
20.
LiYShengAWangY. Synthesis of PID-type controllers without parametric models: a graphical approach. Energy Conversion Manage2008; 49(8): 2392–2402.
21.
KalmanRE. Contribution to the theory of optimal control. Boletin de la Sociedad Matematica Mexicana1960; 5: 102–119.
22.
Kalman RE. On the general theory of control systems. In: 1st IFAC World Congress, Moscow, Russia,1960, pp.481–492.
23.
DoyleJGloverKKhargonekarP. State-space solutions to standard H2 and H∞ control problems. IEEE Trans Automatic Control1989; 34(8): 831–847.
24.
VijaySM. Fuzzy PID controller for multi input multi output model. Int J Adv Eng Technol2011; 2(4): 344–348.
25.
Pelusi D. Improving settling and rise times of controllers via intelligent algorithms. In: 2012 UKSim 14th international conference on computer modelling and simulation, Cambridge, Cambridgeshire UK, 28--30 March 2012, pp.187--192.
26.
GryazinaEN. The D-decomposition theory. Automation Remote Control2004; 65(12): 1872–1884.
27.
Buttini TM and Nicoletti R. Rotor lateral vibration control: a stability and performance analysis based on a model free approach. In: 18th international congress on sound & vibration, Rio de Janeiro, Brazil, 10--14 July 2011, pp.1--8.
28.
Buttini TM and Nicoletti R. Self-identification algorithm for the autonomous control of lateral vibration in flexible rotors. Int J Rotating Machinery 2012; 2012: 1–13. Available at: http://www.hindawi.com/journals/ijrm/2012/873645/cta/.
29.
BristolEH. On a new measure of interaction for multivariable process control. IEEE Trans Automatic Control1966; 11: 133–134.
30.
TrippHMurphyB. Eccentricity measurements on a tilting-pad bearing. ASLE Trans1984; 28(2): 217–224.
31.
Someya T. Journal-bearing databook. Berlin Heidelberg, New York: Springer-Verlag, 1988. ISBN 3-540-17074-X.
32.
WygantKDFlackRDBarrettLE. Influence of pad pivot friction on tilting-pad journal bearing measurements part I: steady operating position. Tribol Trans1999; 42(1): 210–215.
33.
Santos IF. Trends in controllable oil fluid bearings. In: K Gupta (ed.) IUTAM symposium on emerging trends in rotor dynamics, IUTAM Symposium on Emerging Trends in Rotor Dynamics, IUTAM Bookseries 25, New Delhi, India, 23 March--26 March 2009, pp.185--199.
34.
Santos IF and Varela AC. Actively lubricated bearings applied as calibrated shakers to aid parameter identification in rotor dynamics. In: Proceedings of ASME Turbo Expo 2013. San Antonio, Texas, USA, 3--7 June 2013, pp.1–12.
